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NAME

r.droka - Calculates run-out distance of a falling rock mass

KEYWORDS

rock mass, rockfall

SYNOPSIS

r.droka
r.droka --help
r.droka dem=string start=string ang=float red=float m=float num=integer prefix=name [n=integer] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

--overwrite
Allow output files to overwrite existing files
--help
Print usage summary
--verbose
Verbose module output
--quiet
Quiet module output
--ui
Force launching GUI dialog

Parameters:

dem=string [required]
Digital Elevation Model
start=string [required]
Name of starting points map
ang=float [required]
Shadow angle
red=float [required]
Reduction value
Options: 0-1
Default: 0.9
m=float [required]
Value of rock mass (Kg)
num=integer [required]
Number of boulders (>=1)
prefix=name [required]
Prefix for output raster maps
n=integer
Buffer distance (meters)

Table of contents

DESCRIPTION

The intersection between the topographic profile and the line starting from the point of detachment with a certain angle to the horizontal line defines the point of maximum propagation (Evans and Hungr, 1993; Jaboyedoff and Labiouse, 2003). The angle of inclination and the line of propagation are defined as zenith angle and shadow zone. This script defines rockfall zones from a digital elevation model (DEM) and vector layer containing starting point or points.

Energy line used for the cone method from the top or the bottom of a cliff (shadow angle), according to various authors (Image from Jaboyedoff and Labiouse, 2003)

INPUT

Digital Elevation Model = name

Starting points = name

Shadow angle = integer

Reduction value = double

Number of boulders = integer

Rock mass = double

Output prefix = string

Buffer distance = integer

OUTPUT

r.droka generates 5 raster maps and a vector map. The names of all output maps start with the prefix defined by the parameter prefix followed by name of map

REFERENCES

FILIPELLO A., GIULIANI A., MANDRONE G. (2010) - Rock Slopes Failure Susceptibility Analysis: From Remote Sensing Measurements to Geographic Information System Raster Modules. American Journal of Environmental Sciences 6 (6): 489-494, 2010 ISSN 1553-345X 2010 Science Publications.

JABOYEDOFF M., LABIOUSE V. (2003) - Preliminary assessment of rockfall hazard based on GIS Data. Proceeding of the 10th ISRM Congress, South African Inst. Min. Met., Johannesburg, pp: 575-578

EVANS, S.G., HUNGR O. (1993). The assessment of rock fall hazard at the base of the talus slope. Can. Geotech. J., 30: 620-636. DOI: 10.1139/t93-054

SEE ALSO

AUTHORS

Andrea Filipello, University of Turin, Italy

Daniele Strigaro, University of Milan, Italy

SOURCE CODE

Available at: r.droka source code (history)


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© 2003-2018 GRASS Development Team, GRASS GIS 7.4.1svn Reference Manual